This grant request is for basic equipment and supplies necessary for the initial establishment of research facilities with the specific pathogen-free barrier mouse colony under construction at the University of California at Los Angeles, Department of Radiation Onocology. This barrier mouse colony will include a personnel change-area and shower, a washroom and sterilizing area, an isolator room, breeding room, animal holding rooms, irradiation room, and laboratory. Experiments conducted within the barrier research facility will initially be directed toward normal tissue radiobiology, but will become more diversified as the staff is enlarged to include both normal tissue and tumor biology.